As a participating institution in the Primary Breast Cancer Therapy Group (NSABP), the Memorial Cancer Research Foundation of Southern California (MCRFSC) has been contributing data from patients entered into the various group protocols. To date, MCRFSC has entered 145 patients into breast cancer protocols B-05, B-06, B-07, B-08, B-09, and B-10. The MCRFSC is one of the main contributors to NSABP patient data, as evidenced by the fact that during the last grant year period our patient accrual exceeded all other participating institutions. This rate of accrual reflects the participation of the Oncology Network of Southern California (ONSC), the group of academically-oriented private practice oncologists who organized in 1974 to integrate cooperative clinical trials in the community. The MCRFSC provides the mechanism, both feduciary and logistical, for the accrual of patients into NSABP protocols by ONSC members. The present application seeks funding to (1) permit continued patient accrual in current and future protocols, (2) continue the followup of patients entered into protocols which have closed, and (3) collect appropriate biological material and information relevant to such protocols. Protocols B-05 and B-07 are now closed to active treatment so that our patient data consists of biannual followup. The open protocols are: (1) B-06: A trial to compare the worth of segmental mastectomy with and without breast radiation with total mastectomy plus axillary dissection - all patients will undergo axillary dissection and those with histologically positive axillary nodes will receive adjuvant chemotherapy, (2) B-08: A trial to compare the worth of three-drug chemotherapy (L-PAM, 5-FU and Methotrexate) with two-drug chemotherapy (L-PAM and 5-FU), (3) B-09: a trial to determine whether the antiestrogen Tamoxifen when combined with chemotherapy improves the results obtained with chemotherapy alone and (4) B-10: A trial to compare the value of the immunopotentiator C. parvum combined with chemotherapy vs. chemotherapy alone.